Comments on: Which Strugglers Does SIERA Like Besthttp://www.fangraphs.com/fantasy/which-strugglers-does-siera-like-best/
Daily fantasy baseball analysis and strategySun, 02 Aug 2015 22:52:43 +0000hourly1http://wordpress.org/?v=4.1.1By: Jimhttp://www.fangraphs.com/fantasy/which-strugglers-does-siera-like-best/#comment-155019
Tue, 26 Jul 2011 23:57:11 +0000http://www.fangraphs.com/fantasy/?p=21142#comment-155019The guys with higher ERA have the most ‘opportunity’ to improve over the two stats by just subtracting the two numbers. A percentage decrease would probably look very different and would probably include lower ERA pitchers.
]]>By: JKBhttp://www.fangraphs.com/fantasy/which-strugglers-does-siera-like-best/#comment-154930
Tue, 26 Jul 2011 17:31:00 +0000http://www.fangraphs.com/fantasy/?p=21142#comment-154930I’m curious about our ability to decompose “Bad Luck” into % due to high run scoring environment, % due to poor defense, and % due to undefined factors (aka, back luck). Then we would have an idea about how much of the ERA – {FIP,xFIP,SIERA} Delta can realistically be changed by, say, playing half of your games in a different stadium or in front of a different defense, or by your current defense getting better over time either organically or inorganically.

Then we could estimate the probability of change (ERA dropping closer to SIERA, etc…). If Dempster is traded to the Padres next week, we could anticipate the % decrease in Dempster’s ERA if we estimated what % of Dempster’s current Delta was due to his current run scoring environment and defense. However, if none of the defined components of “Bad Luck” change for Dempster, if he is still a Cub and his defense doesn’t get better, then we might assign a lower probability to his rest of season ERA decreasing, because the change would have to come from changes in as yet undefined (unmeasured) factors.

]]>By: John Khttp://www.fangraphs.com/fantasy/which-strugglers-does-siera-like-best/#comment-154836
Tue, 26 Jul 2011 13:02:03 +0000http://www.fangraphs.com/fantasy/?p=21142#comment-154836any concern that it’s identifying all high-era guys?
]]>By: jkbhttp://www.fangraphs.com/fantasy/which-strugglers-does-siera-like-best/#comment-154647
Tue, 26 Jul 2011 01:02:26 +0000http://www.fangraphs.com/fantasy/?p=21142#comment-154647Looks like another statistic that shows how good a pitcher could be in a league average run scoring environment in front of a league average defense
]]>By: theeiffeltowerhttp://www.fangraphs.com/fantasy/which-strugglers-does-siera-like-best/#comment-154581
Mon, 25 Jul 2011 21:23:03 +0000http://www.fangraphs.com/fantasy/?p=21142#comment-154581Dempster’s defense sucks; not sure if you can expect a league average BABIP for him, though I agree that it should come down. Also, is his “bad” HR/FB really just due to bad luck? Dempster hasn’t recorded a season with a sub-11% HR/FB since 2008 and Wrigley has an above-average park factor for HRs. LOB% does look flukishly low though.
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